Description

These routines insert a wchar_t character string (as many wchar_t
characters as will fit on the line) before the character under the
cursor. All characters to the right of the cursor are moved to
the right, with the possibility of the rightmost characters on the line being
lost. The cursor position does not change (after moving to y, x,
if specified). (This does not imply use of the hardware insert character
feature.) The four routines with n as the last argument insert at most
nwchar_t characters. If n<=0, then the entire string is inserted.

If a character in wstr is a tab, newline, carriage return,
or backspace, the cursor is moved appropriately within the window. A newline
also does a clrtoeol(3CURSES) before moving. Tabs are considered to be at
every eighth column. If a character in wstr is another control
character, it is drawn in the ^X notation. Calling winwch(3CURSES) after adding
a control character (and moving to it, if necessary) does not return
the control character, but instead returns the representation of the control character.

RETURN VALUE

All routines return the integer ERR upon failure and an integer value
other than ERR upon successful completion.